U.S. patent application number 14/031227 was filed with the patent office on 2014-04-10 for radiation generating apparatus.
This patent application is currently assigned to CANON KABUSHIKI KAISHA. The applicant listed for this patent is CANON KABUSHIKI KAISHA. Invention is credited to Kazuhiro Matsumoto, Satoru Omura.
Application Number | 20140098942 14/031227 |
Document ID | / |
Family ID | 50432672 |
Filed Date | 2014-04-10 |
United States Patent
Application |
20140098942 |
Kind Code |
A1 |
Omura; Satoru ; et
al. |
April 10, 2014 |
RADIATION GENERATING APPARATUS
Abstract
A radiation generating apparatus comprising: a radiation tube
configured to irradiate radiation; an boom configured to support
the radiation tube; an boom supporting unit configured to support
the boom; a first column linked to the boom supporting unit and
formed in a vertical direction; and a second column extensibly
linked to the first column, the boom comprising a first connecting
unit, and the second column comprising a second connecting unit,
wherein when the boom is folded to the second column upon rotation
about the boom supporting unit, the first connecting unit is
connected to the second connecting unit.
Inventors: |
Omura; Satoru;
(Chigasaki-shi, JP) ; Matsumoto; Kazuhiro;
(Saitama-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
CANON KABUSHIKI KAISHA |
Tokyo |
|
JP |
|
|
Assignee: |
CANON KABUSHIKI KAISHA
Tokyo
JP
|
Family ID: |
50432672 |
Appl. No.: |
14/031227 |
Filed: |
September 19, 2013 |
Current U.S.
Class: |
378/197 |
Current CPC
Class: |
H05G 1/02 20130101; A61B
6/4405 20130101; A61B 6/447 20130101 |
Class at
Publication: |
378/197 |
International
Class: |
H05G 1/02 20060101
H05G001/02 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 5, 2012 |
JP |
2012-223596 |
Claims
1. A radiation generating apparatus comprising: a radiation tube
configured to irradiate radiation; an boom configured to support
said radiation tube; an boom supporting unit configured to support
said boom; a first column linked to said boom supporting unit and
formed in a vertical direction; and a second column extensibly
linked to said first column, said boom comprising a first
connecting unit, and said second column comprising a second
connecting unit, wherein when said boom is folded to said second
column upon rotation about said boom supporting unit, the first
connecting unit is connected to the second connecting unit.
2. The apparatus according to claim 1, wherein the first connecting
unit is configured to move within a specific distance range in a
vertical direction relative to the second connecting unit while
being connected to the second connecting unit.
3. The apparatus according to claim 1, wherein said second column
comprises: a rod configured to come into contact with said first
column; a first compression spring configured to bias said rod in a
first direction in which said first column exists; a contact sensor
configured to detect, when said boom is folded to said second
column upon rotation about said boom supporting unit, contact
between said folded boom and said second column; a plate linked to
said contact sensor; and a second compression spring configured to
bias said plate in a second direction in which said contact sensor
exists, wherein when said plate is biased in a direction opposite
to the second direction as said boom is folded, a taper portion of
said plate comes into contact with a taper portion of said rod to
bias said rod in a direction opposite to the first direction, and
said first column is lifted down.
4. The apparatus according to claim 3, wherein when said plate is
biased in the second direction as said boom spreads out, the taper
portion of said plate separates from the taper portion of said rod,
and said rod is biased in the first direction to lift up said first
column.
5. The apparatus according to claim 1, wherein said second column
comprises: a rod configured to come into contact with said first
column; a first compression spring configured to bias said rod in a
first direction in which said first column exists; a contact sensor
configured to detect, when said boom is folded to said second
column upon rotation about said boom supporting unit, contact
between said folded boom and said second column; a plate configured
to come into contact with said boom; and a second compression
spring configured to bias said plate in a second direction in which
said boom exists, wherein when said plate is biased in a direction
opposite to the second direction as said boom is folded, a taper
portion of said plate separates from a taper portion of said rod to
bias said rod in the first direction, and said first column is
lifted up.
6. The apparatus according to claim 5, wherein when said plate is
biased in the second direction as said boom spreads out, the taper
portion of said plate comes into contact with the taper portion of
said rod, and said rod is biased in a direction opposite to the
first direction to lift down said first column.
7. The apparatus according to claim 1, wherein said boom supporting
unit is configured to move in a vertical direction along said first
column.
8. The apparatus according to claim 7, further comprising a
rotating unit configured to rotatably link said boom supporting
unit to said boom.
9. The apparatus according to claim 8, wherein said boom comprises:
a first spring guide having one end rotatably linked to said boom
supporting unit; a second spring guide having one end rotatably
linked to said boom; and a compression spring linked to the other
end of said first spring guide and the other end of said second
spring guide, wherein said compression spring extends as said boom
is folded and is compressed as said boom spreads out.
10. The apparatus according to claim 1, wherein said boom
supporting unit comprises a protruding portion protruding toward
the inside of said first column, said first column comprises a hook
portion configured to hook on the hook portion, a cam linked to the
hook portion, and a rotating shaft portion configured to rotate the
hook portion and the cam, said boom supporting unit is configured
to move along said first column, and the cam comes into contact
with part of said first column while the protruding portion is
hooked on the hook portion upon movement of said boom supporting
unit.
11. The apparatus according to claim 10, wherein a resistance
against a force to move said boom supporting unit along said first
column is lower than a resistance against a force to move said
first column along said second column.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a radiation generating
apparatus.
[0003] 2. Description of the Related Art
[0004] Recently, as medical X-ray imaging apparatuses, there have
been widely used a movable X-ray imaging cart which performs X-ray
imaging in a hospital room or operating room and an apparatus which
holds an X-ray tube which irradiates X-rays and an X-ray detector
which detects the X-rays transmitted through a patient by using a
C-boom.
[0005] When performing X-ray imaging by using the movable X-ray
imaging cart, it is necessary to use an arrangement for changing
the position of an X-ray tube on a bed to place the X-ray tube
above an object lying on the bed. When imaging the four limbs of
the object, in particular, it is impossible to keep properly
positioning an X-ray detector and an X-ray tube and to capture a
proper image unless it is possible to place the X-ray tube at any
position on the bed.
[0006] In addition, the movable X-ray imaging cart runs through the
narrow space between beds in a hospital room and on corridors
between hospital wards along which stretchers and other medical
apparatuses come and go, and hence needs to be folded into a
compact structure when moving. For this purpose, this apparatus
needs to be configured such that the boom holding the X-ray tube
can be widely spread out at the time of X-ray imaging and can be
accommodated in small size at the time of movement.
[0007] In the X-ray generating apparatus disclosed in Japanese
Patent Laid-Open No. 2007-185514, a link type boom which supports
an X-ray tube is configured to rotate about one end of the boom
from an angle vertical to the ground or an angle near it. With this
operation, the boom is spread out by rotation at the time of
imaging and is accommodated by the reverse operation at the time of
movement.
[0008] In addition, in X-ray imaging in an orthopedic surgery or
the like, a high importance is placed especially on an SID (Source
Image Distance) between a focal point and an image reception plane.
When performing imaging operation using a movable X-ray imaging
cart, therefore, it is necessary to adjust the X-ray tube in the
height direction after adjustment of the X-ray tube in the
horizontal direction in order to accurately adjust the SID when
setting the X-ray tube.
[0009] According to the X-ray generating apparatus disclosed in
Japanese Patent Laid-Open No. 2007-185514, however, as the X-ray
tube is moved in the height direction, the X-ray tube is also moved
in the horizontal direction. This makes it difficult to perform
proper positioning.
SUMMARY OF THE INVENTION
[0010] In consideration of the above problem, the present invention
provides a technique which can adjust the position of a radiation
tube such as an X-ray tube in the height direction without changing
the position in the horizontal direction when positioning the
tube.
[0011] According to one aspect of the present invention, there is
provided a radiation generating apparatus comprising: a radiation
tube configured to irradiate radiation; an boom configured to
support the radiation tube; an boom supporting unit configured to
support the boom; a first column linked to the boom supporting unit
and formed in a vertical direction; and a second column extensibly
linked to the first column, the boom comprising a first connecting
unit, and the second column comprising a second connecting unit,
wherein when the boom is folded to the second column upon rotation
about the boom supporting unit, the first connecting unit is
connected to the second connecting unit.
[0012] Further features of the present invention will be apparent
from the following description of exemplary embodiments with
reference to the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIGS. 1A and 1B are views showing the arrangement of an
X-ray generating apparatus according to the first embodiment;
[0014] FIGS. 2A and 2B are views for explaining an accommodation
mechanism according to the first embodiment;
[0015] FIGS. 3A and 3B are views for explaining an accommodation
mechanism according to the second embodiment;
[0016] FIGS. 4A and 4B are views for explaining an accommodation
mechanism according to the third embodiment;
[0017] FIGS. 5A and 5B are views showing the arrangement of a
movable X-ray generating apparatus according to the fourth
embodiment;
[0018] FIG. 6 is a view for explaining an extensible column
according to the fourth embodiment;
[0019] FIG. 7 is a flowchart showing a procedure for processing
executed by using the X-ray generating apparatus according to the
fourth embodiment; and
[0020] FIGS. 8A to 8C are views for explaining a connecting
mechanism for an boom and a column according to the fifth
embodiment.
DESCRIPTION OF THE EMBODIMENTS
[0021] An exemplary embodiment(s) of the present invention will now
be described in detail with reference to the drawings. It should be
noted that the relative arrangement of the components, the
numerical expressions and numerical values set forth in these
embodiments do not limit the scope of the present invention unless
it is specifically stated otherwise.
First Embodiment
[0022] An X-ray generating apparatus will be described below as an
example of a radiation generating apparatus. However, the type of
radiation to be used is not limited to X-rays. It is possible to
use other types of radiation such as .alpha.-rays, .beta.-rays, and
.gamma.-rays. The arrangement of a movable X-ray generating
apparatus according to the first embodiment of the present
invention will be described with reference to FIGS. 1A and 1B. FIG.
1A shows the form of the X-ray generating apparatus at the time of
movement. FIG. 1B shows the form of the apparatus when the boom
extends at the time of imaging.
[0023] The movable X-ray generating apparatus includes an X-ray
tube 1 (radiation tube), an boom 2, a first column 3, an boom
supporting unit 4, a second column 5, a cart unit 6, a moving
mechanism 7, a handle 8, a monitor 9, a first connecting unit 10,
and a second connecting unit 11.
[0024] The X-ray tube 1 irradiates X-rays. The boom 2 supports the
X-ray tube 1. The first column 3 is a column which supports the
boom 2. The boom supporting unit 4 is configured to link the boom 2
to the first column 3 and allow the boom 2 to open/close with
respect to the first column 3. The boom supporting unit 4
incorporates a taper pulley to keep the force applied by the
operator to close/close the boom 2 constant. The force generated by
the boom 2 or a spring or weight in the first column 3 is
transmitted to the taper pulley through a wire.
[0025] The second column 5 is a column which allows the first
column 3 to move in a direction perpendicular to the ground. That
is, the first column 3 is extensible relative to the second column
5. The second column 5 incorporates an electromagnetic holder in
contact with the surface of the first column 3. A portion of the
first column 3 with which the electromagnetic holder comes into
contact is formed from a magnetic metal. While the electromagnetic
holder is energized, the extension/contraction of the first column
3 is locked. Although not shown, a signal input unit for switching
the energized state of the electromagnetic holder is formed near
the X-ray tube 1.
[0026] The cart unit 6 supports the second column 5. A spring or
weight for making the boom 2 described above spread out may be
located in the second column 5 or the cart unit 6 because power can
be transmitted to the first column 3 by any combination of a
pulley, a wire, a ball screw, and a gear. The moving mechanism 7
allows the cart unit 6 to move on the ground. The moving mechanism
7 can move the cart unit 6 by rotating a plurality of tires or
casters while they are placed on the ground. The handle 8 is
provided on the cart unit 6. When moving the apparatus, the
operator operates the moving direction of the apparatus while
gripping the handle 8. The monitor 9 is installed on the upper
surface of the cart unit 6. The monitor 9 displays the information
and position of a patient to be imaged at the time of doctor's
round and a captured image. When accommodating the X-ray tube 1,
the operator connects the first connecting unit 10 to the second
connecting unit 11. When moving the apparatus while the boom 2 is
folded toward the first column 3 or the second column 5 or not
using the apparatus, the movement of the boom 2 and first column 3
is limited to prevent them from spreading out beyond a
predetermined range. The first connecting unit 10 is provided on
the boom 2 side, and the second connecting unit 11 is provide on
the second column 5 side.
[0027] A concrete arrangement of the accommodation mechanism will
be described next with reference to FIGS. 2A and 2B. FIG. 2A shows
a concrete side surface shape of the accommodation mechanism. FIG.
2B shows a concrete sectional shape of the accommodation mechanism.
The first connecting unit 10 on the boom side includes a base
portion 12, pawl portions 13, rotating shaft portions 14, and
rollers 15.
[0028] The base portion 12 is fixed to the boom 2. Each pawl
portion 13 includes a projection portion on the distal end side
surface. The pawl portions 13 have projections formed on the two
ends of the base portion 12 to face each other. Each pawl portion
13 rotates about the corresponding rotating shaft portion 14
relative to the base portion 12. The rotating shaft portions 14 are
provided with springs, which apply a force to rotate (bias) the
pawl portions 13 in FIG. 2B so as to sandwich the second connecting
unit 11 on the column side. Each roller 15 is provided in the pawl
portion 13 so as to partly expose.
[0029] The second connecting unit 11 on the column side has a U
shape. The protruding portions on the two ends of the second
connecting unit 11 are fixed to a side surface of the second column
5 with screws or an adhesive. With this arrangement, folding the
boom 2 to the column side will connect the first connecting units
10 on the boom side to the second connecting unit 11 so as to
sandwich the second connecting unit 11 on the column side. Since
the rollers 15 are in contact with the second connecting unit 11 on
the column side, the first connecting units 10 on the boom side can
slide/move along the second connecting unit 11 on the column side
with a specific distance range. To facilitate sliding/moving,
grooves for guiding the rollers 15 may further be formed on the
second connecting unit 11 on the column side.
[0030] The extensible range of the first column 3 with the first
connecting units 10 being connected to the second connecting unit
11 is defined by the mount position of the second connecting unit
11 on the column side and the length of the U shape of the second
connecting unit 11 on the column side in the vertical direction.
This limits the movement of the first column 3 so as to inhibit it
from moving to the upper and lower end portions of the extensible
range. Note that the shapes of the first connecting units 10 on the
boom side and second connecting unit 11 on the column side may be
reversed.
[0031] With the above arrangement, the operator spreads the folded
boom and positions the X-ray tube relative to an imaging
irradiation field in the horizontal direction. The operator then
releases the extension/contraction lock of the first column by
operating the signal input unit provided near the X-ray tube. This
makes it possible to change the height of the X-ray tube in the
vertical direction while maintaining its horizontal position. This
can easily and accurately match the irradiation field with the SID
at the time of X-ray imaging, thereby providing an X-ray generating
apparatus which improves the operability for the operator. Note
that the arrangement described in the first embodiment may be
implemented in each embodiment described later.
Second Embodiment
[0032] The arrangement of an accommodation mechanism according to
the second embodiment of the present invention will be described
with reference to FIGS. 3A and 3B. FIG. 3A shows a state in which
an boom is accommodated. FIG. 3B shows a state in which the boom
spreads out.
[0033] The second embodiment will exemplify an arrangement in which
as the boom spreads out, the column is automatically lifted up. The
same reference numerals as in the first embodiment denote the same
components in the second embodiment, and a description of them will
not be repeated.
[0034] A second column 5 includes a first compression spring 16, a
rod 17, a second compression spring 18, a plate 19, and a contact
sensor 20. One end of the first compression spring 16 is fixed to
the bottom portion of the second column 5. The rod 17 is a rod for
lifting up a first column 3, and has a taper portion formed on part
of a side surface of the rod. The rod 17 is connected to the other
end of the first compression spring 16 and is biased by the first
compression spring 16 in the first direction in which the first
column 3 exists. One end of the second compression spring 18 is
fixed to an inner surface portion of the second column 5. The plate
19 is a plate for limiting the movable range of the rod 17, and has
a hole with a taper portion formed on part of the plate. The rod 17
passes through this hole. The plate 19 is biased by the second
compression spring 18 in the second direction in which the contact
sensor 20 exists. The taper portions of the rod 17 and plate 19
come into contact with each other at different positions. This
defines the positional relationship between the rod 17 and the
plate 19.
[0035] As the operator folds an boom 2, the plate 19 is biased in a
direction (a direction in which the second compression spring 18
exists) opposite to the second direction. In accordance with this
operation, the taper portion of the plate 19 comes into contact
with the taper portion of the rod 17 to bias the rod 17 in a
direction (a direction in which the first compression spring 16
exists) opposite to the first direction, thereby lifting down the
first column 3. As the boom 2 spreads out, the plate 19 is biased
in the second direction. In accordance with this operation, the
position of the taper portion of the plate 19 shifts from the
position of the taper portion of the rod 17. As a result, they are
brought into a noncontact state, and the rod 17 is biased in the
first direction to be lifted up. In accordance with this operation,
the first column 3 is lifted up. The contact sensor 20 detects
contact or noncontact with the boom 2 to detect whether the boom 2
is spread out or folded. A control unit (not shown) which a cart
unit 6 includes detects, based on the detection result obtained by
the contact sensor 20, that the boom 2 is spread out, and locks the
extension/contraction of the first column 3 by the electromagnetic
lock of the second column 5 after the first column 3 is lifted up
for a predetermined time.
[0036] With the above arrangement, the operator spreads the folded
boom and positions the X-ray tube relative to an imaging
irradiation field in the horizontal direction after the first
column 3 is lifted up. The operator then releases the lock of the
first column 3 by operating the signal input unit provided near the
X-ray tube. This makes it possible to change the height of the
X-ray tube in the vertical direction while maintaining its
horizontal position. When the first column 3 is to be further
lifted up, the length of each taper portion may be increased or a
reduction gear may be provided between the rod 17 and the first
column 3. This makes it possible to accommodate the boom while the
first column is located at the lowest position, thereby providing
an X-ray generating apparatus with good forward visibility at the
time of movement.
Third Embodiment
[0037] The arrangement of an accommodation mechanism according to
the third embodiment of the present invention will be described
with reference to FIGS. 4A and 4B. FIG. 4A shows a state in which
an boom is spread out. FIG. 4B shows a state in which the boom is
accommodated.
[0038] The third embodiment will exemplify an arrangement in which
as the boom is folded, a column is automatically lifted down. The
same reference numerals as in the first and second embodiments
denote the same components in the third embodiment, and a
description of them will not be repeated.
[0039] A second column 5 includes a first compression spring 16, a
second compression spring 18, a rod 21, a plate 22, and a contact
sensor 23. The rod 21 is a rod for lifting up a first column 3. A
taper portion is formed on part of a side surface of the rod 21.
The rod 21 is connected to one end of the first compression spring
16. The plate 22 is a plate for limiting the movable range of the
rod 21, and is configured to partly come into contact with an boom
2. A hole having a taper portion is formed in part of the plate 22.
The rod 21 passes through the hole. The taper portions of the rod
21 and plate 22 come into contact with each other at different
positions. This defines the positional relationship between the rod
21 and the plate 22. The contact sensor 23 detects contact with the
plate 22 to detect that the boom 2 is folded and accommodated and
has come into contact with part of the plate 22 which protrudes
from the second column 5.
[0040] When the boom 2 is thus folded and accommodated from the
spread state, the taper portion of the plate 22 shifts and the
first compression spring 16 lifts up the rod 21. The control unit
of a cart unit 6 detects, based on the detection result obtained by
the contact sensor 23, that the boom 2 is accommodated, and
releases the extension/contraction lock of the first column 3 by
using the electromagnetic lock of the second column 5. As the rod
21 is lifted up, the first column 3 is lifted up. When the bottom
portion of the first column 3 exists at a position higher than the
upper distal end of the rod 21 at the time of the accommodation of
the boom 2, the bottom portion of the first column 3 is lifted
down, under its own weight, to the distal end of the upper portion
of the rod 21 after the control unit releases the
extension/contraction lock of the first column 3.
[0041] With the above arrangement, accommodating the boom from the
spread state will automatically adjust the first column at the
accommodation position. This makes it possible to smoothly position
the X-ray tube when performing next imaging operation, thereby
providing an X-ray generating apparatus which has improved the
operability for the operator.
Fourth Embodiment
[0042] The arrangement of a movable X-ray generating apparatus
according to the fourth embodiment of the present invention will be
described with reference to FIGS. 5A and 5B. FIG. 5A shows a state
in which the apparatus is moving. FIG. 5B shows the movable X-ray
generating apparatus with its boom extending at the time of X-ray
imaging. The same reference numerals as in the first to third
embodiments denote the same components in the fourth embodiment,
and a description of them will not be repeated.
[0043] The X-ray generating apparatus includes an X-ray tube 1, an
boom 2, a first column 3, a second column 5, a cart unit 6, a
moving mechanism 7, a handle 8, a monitor 9, an boom supporting
unit 24, and a column rotating unit 25.
[0044] The boom supporting unit 24 is configured to link the boom 2
to the first column 3 and allow the boom 2 to open/close with
respect to the first column 3. The boom supporting unit 24 is
configured to be movable on the first column 3 in a direction
vertical to the ground. The column rotating unit 25 links the cart
unit 6 to the second column 5 and allows the second column 5 to
rotate on the cart unit 6 about an axis perpendicular to the ground
by using a bearing. The column rotating unit 25 is provided with a
non-excitation brake to stop the rotation of the second column 5 at
an arbitrary position while the non-excitation brake is
energized.
[0045] FIG. 6 shows a concrete arrangement of an extensible column.
The boom 2 includes a compression spring 27, a first spring guide
28, and a second spring guide 29. The boom supporting unit 24
includes cam followers 35, and is linked to the boom 2 through a
rotating unit 26. The first column 3 includes a small-diameter
pulley 30, a taper pulley 31, a first wire 32, a tension spring 33,
a second wire 34, and slide guide plates 36. The second column 5
includes a small-diameter pulley 37, a taper pulley 38, a third
wire 39, a tension spring 40, a fourth wire 41, a linear guide 42,
a linear guide rail 43, and a stopper 44. Each constituent element
will be described below.
[0046] The rotating unit 26 links the boom 2 to the boom supporting
unit 24. As the rotating unit 26 rotates, the boom 2 rotates
relative to the boom supporting unit 24. The compression spring 27
is formed from an elastic member such as a metal spring or rubber.
When the boom 2 is to be formed as a thinner member, a gas spring
may be used instead of the compression spring 27. One end of the
first spring guide 28 is configured to rotate on the boom
supporting unit 24. One end of the second spring guide 29 is
configured to rotate on the boom 2. The compression spring 27 is
linked to the other end of the first spring guide 28 and the other
end of the second spring guide 29.
[0047] As the operator spreads the boom 2 from the folded and
accommodated state to a horizontal posture, the compression spring
27 is compressed. This produces a force to restore the boom 2 to an
accommodated state, and hence the operator can switch the
accommodated state of the boom 2 to the spread state or the other
way around.
[0048] The small-diameter pulley 30 is provided on an upper portion
in the first column 3. The taper pulley 31 is coaxial with the
small-diameter pulley 30. One end of the first wire 32 is fixed to
the boom supporting unit 24, and the other end is wound around the
taper pulley 31. One end of the second wire 34 is connected to the
tension spring 33, and the other end is wound around the
small-diameter pulley 30. The taper angle of the taper pulley 31 is
set to an angle that balances the weight of the members provided
between the boom supporting unit 24 and the X-ray tube 1 with the
force of the tension spring 33 regardless of whether the length of
the tension spring 33 changes. The cam followers 35 are provided on
the boom supporting unit 24.
[0049] The slide guide plates 36 are provided in the first column 3
so as to sandwich the cam followers 35. The surfaces of the slide
guide plates 36 with which the cam followers 35 come into contact
are preferably formed as smooth as possible to allow the cam
followers 35 to slide smoothly. This makes it possible to lift up
the boom 2 in a direction vertical to the ground along the first
column 3 by applying predetermined small force to the members
provided between the boom supporting unit 24 and the X-ray tube 1
by using the force of the tension spring 33. Providing the cam
followers 35 and the slide guide plates 36 can lift up the boom
supporting unit 24 on the first column 3 without changing the angle
relative to the first column 3.
[0050] The small-diameter pulley 37 is provided on an upper portion
in the second column 5. The taper pulley 38 is coaxial with the
small-diameter pulley 37. One end of the third wire 39 is fixed to
the bottom portion of the first column 3, and the other end is
wound around the taper pulley 38. One end of the fourth wire 41 is
connected to the tension spring 40, and the other end is wound
around the small-diameter pulley 37. The taper angle of the taper
pulley 38 is set to an angle that balances the weight of the
members provided between the first column 3 and the X-ray tube 1
with the force of the tension spring 40 regardless of whether the
length of the tension spring 40 changes. The linear guide 42 is
provided on the bottom portion of the first column 3.
[0051] The linear guide rail 43 is provided in the second column 5
so as to guide the linear guide 42. This makes it possible to lift
up the first column 3 by applying a predetermined small force to
the members provided between the first column 3 and the X-ray tube
1 with the force of the tension spring 40. Providing the linear
guide 42 and the linear guide rail 43 can lift up the first column
3 in a direction vertical to the ground along the second column 5.
The stopper 44 is preferably provided on a side of the linear guide
rail 43 and formed from a solenoid. Energizing the stopper 44 will
make a projection appear on the linear guide rail 43 to inhibit the
linear guide 42 from sliding on the linear guide rail 43. This
limits the slide range of the linear guide 42 and limits the
extension/contraction range of the first column 3 relative to the
second column 5.
[0052] A procedure for processing executed by the X-ray generating
apparatus according to the fourth embodiment of the present
invention will be described below with reference to the flowchart
of FIG. 7.
[0053] In step S701, the operator moves the X-ray tube 1 to
position the X-ray tube 1 relative to an imaging irradiation field
in the horizontal direction. In step S702, the control unit of the
cart unit 6 determines whether a column extension/contraction
signal from the signal input unit described in the first embodiment
has been detected. The operator generates signals by using the
signal input unit in accordance with the position of the boom 2 on
the first column 3 and the position of the first column 3 on the
second column 5. If the control unit determines that a column
extension/contraction signal is detected (YES in step S702), the
process advances to step S703. If the control unit determines that
no column extension/contraction signal is detected (NO in step
S702), the control unit waits until the detection of the above
signal.
[0054] In step S703, the control unit of the cart unit 6 releases
the column extension/contraction lock by switching the energization
of the stopper 44 to extend the slide area of the linear guide 42.
In step S704, the operator positions the X-ray tube 1 in the height
direction. Thereafter, the apparatus shifts to X-ray imaging.
[0055] With the above arrangement, in X-ray imaging operation using
a link boom which can move on the column in the vertical direction,
it is possible to change the height of the X-ray tube while
maintaining its horizontal position at any position in the movable
range. This can easily and accurately match the irradiation field
with the SID at the time of X-ray imaging, thereby providing an
X-ray generating apparatus which improves the operability for the
operator.
Fifth Embodiment
[0056] The arrangement of a connecting mechanism for an boom and a
column according to the fifth embodiment of the present invention
will be described with reference to FIGS. 8A to 8C. FIG. 8A shows a
state in which the boom moves at a position lower than the lowest
height of the first column. FIG. 8B shows a state in which the boom
moves at a position higher than the lowest height of the first
column. FIG. 8C shows a state in which the boom is located at the
highest position.
[0057] The fifth embodiment will exemplify an arrangement which
inhibits the column from moving to a position higher than the boom
during extension/contraction of the column. The same reference
numerals as in the first to fourth embodiments denote the same
components in the fifth embodiment, and a description of them will
not be repeated.
[0058] An boom supporting unit 24 includes a protruding portion 45.
A first column 3 includes a hook portion 46, a cam 47, and a
rotating shaft portion 48. The protruding portion 45 protrudes from
the boom supporting unit 24 toward the inside of the first column
3. The protruding portion 45 moves, together with the boom
supporting unit 24, in the vertical direction along the first
column.
[0059] The hook portion 46, the cam 47, and the rotating shaft
portion 48 are provided in the first column 3. The hook portion 46
is shaped to be hooked on the protruding portion 45 as it moves.
The hook portion 46 and the cam 47 rotate about the rotating shaft
portion 48. The rotating shaft portion 48 has rotational resistance
due to friction, and the hook portion 46 and the cam 47 are
structured not to rotate due to the self weights. The cam 47 has a
portion which comes into contact with part of the first column 3 as
the cam rotates. This portion is provided with a rubber member or
elastic member to further add resistance to the rotation of the
hook portion 46 and cam 47.
[0060] The hook portion 46, the cam 47, and the rotating shaft
portion 48 are positioned such that when the protruding portion 45
hooks on the hook portion 46 and the cam 47 comes into contact with
the first column 3, the highest position of the boom is equal to or
higher than the highest position of the column in a contraction
state. In addition, in this embodiment, the resistance against the
force to move the boom supporting unit 24 on the first column 3 is
configured to be smaller than the resistance against the force to
move the first column 3 on a second column 5. With this
arrangement, when the height position of an X-ray tube is to be
changed, the vertical movement of the boom supporting unit 24
relative to the first column 3 is performed in preference to the
vertical movement of the first column 3 relative to the second
column 5.
[0061] With the above arrangement, when the protruding portion 45
is located at a position lower than the hook portion 46, the
extensible column contracts to the highest degree. In this state,
moving the boom supporting unit 24 on the first column 3 will
change the height of the X-ray tube. When the protruding portion 45
hooks on the hook portion 46, the cam 47 stops the movement of the
boom supporting unit 24, and the first column 3 moves on the second
column 5 to change the height of an X-ray tube 1.
[0062] While the column extends to the highest degree, when the
protruding portion 45 moves to a position higher than the hook
portion 46, the boom supporting unit 24 moves further upward on the
first column 3 to raise the X-ray tube. This inhibits the column
from being located higher than the boom, and hence the operator can
perform operation in consideration of only the maximum height of
the boom.
[0063] This embodiment is constituted by only mechanisms. However,
in order to obtain the same effect, the embodiment may provide a
system which detects the height of the boom at the highest point
and the height of the column at the highest point, and electrically
brakes a mechanism for moving the boom and the column in the height
direction when the height of the column at the highest point
exceeds the height of the boom at the highest point. In addition,
although the embodiment gives consideration to the highest position
of the boom and the highest position of the column, the highest
position of the X-ray tube may be regarded as the highest position
of the boom.
[0064] With the above arrangement, the operator can easily pay
attention to an object even while handling the boom and the X-ray
tube. This can improve the operability for the operator and perform
X-ray imaging while quickly responding to a change of the
object.
[0065] Note that the above embodiments may be executed
independently or in combination.
[0066] According to the present invention, when positioning a
radiation tube, it is possible to adjust the position of the tube
in the height direction without changing its position in the
horizontal direction.
Other Embodiments
[0067] Aspects of the present invention can also be realized by a
computer of a system or apparatus (or devices such as a CPU or MPU)
that reads out and executes a program recorded on a memory device
to perform the functions of the above-described embodiment(s), and
by a method, the steps of which are performed by a computer of a
system or apparatus by, for example, reading out and executing a
program recorded on a memory device to perform the functions of the
above-described embodiment(s). For this purpose, the program is
provided to the computer for example via a network or from a
recording medium of various types serving as the memory device (for
example, computer-readable storage medium).
[0068] While the present invention has been described with
reference to exemplary embodiments, it is to be understood that the
invention is not limited to the disclosed exemplary embodiments.
The scope of the following claims is to be accorded the broadest
interpretation so as to encompass all such modifications and
equivalent structures and functions.
[0069] This application claims the benefit of Japanese Patent
Application No. 2012-223596 filed on Oct. 5, 2012, which is hereby
incorporated by reference herein in its entirety.
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